Grinding wheel dressing device



April 29, 1958 c. H. NEWBOULD 2,832,329

- GRINDING WHEEL DRESSING DEVICE Filed. Dec. 5, 1955 2 Sheets-Sheet 1 2IN V EN TOR. (mass u. NEH/500w Way AT TORNE Y Ap 29, 1953 c. H. NEWBOULD2,832,329

GRINDING WHEEL DRESSING DEVICE 2 Sheets-Shet 2 Filed Dec. 5, 1955INVENTOR. CHARLES M/VEWBOULD BY 2 A TTORNEY United States Patent fGRHNDING WHEEL DRESSING DEVICE Qlrarles H. Newbould, York, Pa.

Application December 5, 1955, Serial No. 550,950

t Claims. (Cl. 125-11) This invention relates to improvements in agrinding wheel dressing device and, more particularly, to a grindingwheel dressing device for use with various types of grinding machinessuch as surface grinders, cutter grinders, and the like.

A typical type of grinding wheel dressing device in use at presentcomprises a simple bar member having a diamond member fixedly positionedthereon so as to project at right angles from one surface of the bar.Particularly where such a dressing device is to be used to dress thecurved face of a grinding wheel of a surface grinder having a magneticchuck, the bar is placed upon the chuck and the latter is energized tohold the bar attached to the chuck. The diamond dressing tool thenprojects vertically from the chuck and the grinding wheel is loweredinto contact with the diamond tool whereby, when the grinding wheel isrotated and the chuck is reciprocated horizontally upon its ways,dressing of the wheel takes place. However, under circumstances where itis necessary to dress a grinding wheel in the midst of a grindingoperation, moving the wheel from its operative position into contactwith the dressing tool presents the difficulty of restoring the grindingwheel to its operative position. Assuming that only a very limitedamount of additional grinding was necessary to complete the grindingoperation, the operator would have to blue the surface and carefullyrestore the grinding wheel into desired operative position to preventthe possibility of grinding the surface too much.

From the foregoing, it will be seen that the common practice is to movethe grinding Wheel to the dressing tool rather than vice versa. Someattempts have been made to devise grinding Wheel dressing fixtures ortools wherein the dressing tool head which holds the dressing diamond,for example, is moved into engagement with the dressing wheel ratherthan vice versa. However, these devices principally have been quiteelaborate, complicated, and hence relatively expensive, therebydeterring wide sale thereof.

It is the principal object of the present invention to provide agrinding wheel dressing device in which the holder for the dressing toolsuch as a diamond tool member is adjustably movable relative to a basemember and when the dressing tool head has been moved into desiredrelationship to the wheel it is to dress, the adjustable members of thedevice are then locked in operative position while the base member isheld attached for example to a magnetic chuck of a surface grinder, orthe like. The connected elements which comprise the entire dressingdevice are relatively few in number, simple in construction, easilyassembled, sturdy and durable so as to provide long life, and may bemanufactured at a cost to permit the sale thereof for substantially lessthan.

adjustable dressing devices presently available on the market.

Another object of the invention is to provide a base member having aplurality of supporting surfaces thereon which selectively may bedisposed against the flat sup- 2,332,329 Patented Apr. 29, 1958 portingsurface of a magnetic chuck for example and the pivot for an adjustablypositionable arm on the base member is disposed at different distancesfrom said sev eral surfaces on the base member, whereby said pivot mayselectively be disposed at different distances above the supportingsurface of the magnetic chuck, thus providing a construction in which asupporting arm of limited length may be utilized to nevertheless afforda substantial range of positions for the tool holding head above thesupporting surface on the grinding machine.

Details of these objects and of the invention, as well as other objectsthereof, are set forth in the following specification and illustrated inthe accompanying drawings comprising a part thereof.

In the drawings:

Fig. 1 is an end elevation of an exemplary surface grinder selected forpurposes of illustrating a typical use of a grinding wheel dressingdevice embodying the principles of the present invention. In this viewthe side of the Wheel is being dressed.

Fig. 2 is a view of the structure shown in Fig. l as seen at to theposition shown in Fig. l and wherein the dressing device is seen in endelevation.

Fig. 3 is an enlarged sectional View showing a fragmentary portion ofthe dressing device embodying the principles of the invention, said viewbeing taken along the line 3-3 of Fig. 1 and being on a larger scalethan Fig. l.

Fig. 4 is a view similar to Fig. 2 but showing the dress ing devicepositioned at 90 to the view shown in Fig. 2 so as to position thedressing tool against the curved face of the grinding wheel, whereas inthe other figures the dressing device is positioned to dress the side ofthe grinding wheel.

For purposes of simplifying the illustration and description of thepresent invention, an exemplary surface grinder has been selected forpurposes of describing the details and function of a dressing deviceembodying the present invention relative to the grinding wheel of such agrinding machine. However, it is to be understood that the inventiondevice may be used with other types of grinders such as cutter grindersand the like. Referring to Figs. 1, 2 and 4, an exemplary magnetic chuck10 is shown and upon the upper or working surface thereof is positioneda grinding wheel dressing device 12 embodying the principles of thepresent invention. A typical grinding wheel 14, which is to be dressed,is rotatably supported by an arbor 16. Current supplied to the magnetsof the chuck 10 is controlled by a conventional switch operating handle18.

Referring to Figs. 1 through 3, the wheel dressing device 12 ispositioned to grind the side of the grinding wheel 14. Said dressingdevice comprises a base member 20 which, for example, may be formed froma suitable casting of steel or iron. Said base member has two flatsurfaces 22 and 24 which extend transversely to the main plane of thebase member 20 along different edges thereof. Said flat surfaces are ata right angle to each other and may be either continuous along theentire edges of the base member or the same may be interrupted, asclearly shown in Figs. 1 and 4, by notches 26 and 23. Also, thetransverse width of fiat surfaces 22 and 2d, viewed in Pig. 2, is muchless than the length thereof viewed in Fig. 1, whereby regardless ofwhether surface 22 or 24 is resting upon the face of chuck it],relatively little space is occupied by the dressing device 12 so not tointerfere with a Work-piece already positioned up on the chuck It] to beground by wheel lid.

Base member 26 also is provided with hearing means comprising atransverse bearing aperture 3%, the axis of which is parallel to thefiat surfaces 22 and 24. Further, the bearing aperture 35b is positionedfarther from the 3 flat surface 24 than the flat surface 22 as isclearly shown in Figs. 1 and 4, but in both instances, the axis ofaperture 30 is spaced from the surfaces 22 and 24 a distance less thanhalf the lengths of said surfaces.

Extending through base member is an arcuate slot 32 which comprises asegment of a circle having the axis of bearing aperture as a center.Further, in casting the base member 20, it is preferred that the slot 32be outlined by a flange 34 which may be suitably finished by machiningor grinding so as to present a smooth flat planar surface disposedoutwardly from the portion of the base member immediately adjacent theslot 32. Said portion incidentally maybe made substantially thinner thanthe width of the flanges projecting from adjacent edges thereof and uponwhich the flat surfaces 22 and 24 are formed as is apparent from Fig. 2.Hence, the base member 20 may be cast from iron or steel so as to berelatively light in weight and economical in consumption of material.

The dressing device also comprises an arm 35 which has bearing means atone end cooperating with the hearing aperture 30, said means comprisinga cylindrical shaft or pin 38 which is fitted within aperture 30 so asto be smoothly rotatable therein without appreciable looseness.intermediately of the ends of arm 36, locking means project from the onesurface thereof in the form of a threaded pin 44) which extends througharcuate slot 32. One surface of arm 36 slidably abuts against the smoothsurface of one face of flange 34, while a threaded thumb nut 42 isengageable With the opposite smooth surface of flange 34 when threadedonto pin for purposes of locking arm 36 in any desired position aboutthe axis of bearing means 30 and 38.

The outer end of arm 36 also is provided with hearing means comprising abearing aperture 44 which is parallel to the pins 38 and 40 for purposesof receiving a hearing shaft 46 which projects from one face of arotatably supported tool holding head 48. Said head is provided with atool receiving hole 50 which may be complementary in shape to anydesired type of dressing tool 52 to be held therein. One common form ofdressing tool 52 comprises a cylindrical shank having a diamond tip 54.The tool 52 may be held in operative position by any conventional meanssuch as headless set screws 56, whereby the tool 52 may be rotated aboutits axis within head 48 from time to time in order that the diamond tip54 may be maintained in sharp condition. Further, it will be noted thatthe axis of the tool receiving hole 50 is disposed at an angle otherthan 90 to the axis of shaft 46, thereby further facilitating themaintaining of d the diamond tip in sharp condition. The tool holdinghead 48 may be locked in any angular position relative to arm 36 bymeans of a suitable thumb nut 58 threaded onto the outer end of shaft46.

Due to the range of movement afforded the arm 36 relative to the basemember 20, and also the pivotal support of the head 48 by the outer endof said arm, as well as the different spacings of the axis of thebearing means 39 and 38 respectively away from the flat surfaces 22 and24, a substantial range of different positions of the dressing tool 52relative to a grinding wheel as Well as the supporting surface for thedressing device are aiforded. For example, when the dressing tool is tobe positioned relative to the chuck 10 so as to dress the side of agrinding wheel 14 as shown in Figs. 1 and 2, it may be desirable toafford greater spacing of the axis of bearing means 30 and 38 from theupper face of chuck 10, whereby the flat surface 24 is disposed againstthe upper face of chuck 10. The arm 36 is then suitably moved about theaxis of bearing aperture 30 so as further to dispose the tool holdinghead 48 at a desired elevation relative to grinding wheel 14. Then, thelocking means comprising thumb nut 42 is tightened to hold the arm 36 insaid desired position of operation relative to base member 20. Inaddition, by loosening thumb nut 58, head 48 may be rotated to disposethe tip 54 of dressing tool 52 in desired position relative to the sideof grinding wheel 14 as shown in Figs. 1 through 3, following which thethumb nut 58 is tightened and, in the event the current to the magnetswithin the chuck ltl has not been turned on, it then may be caused toenergize the magnet by operating switch handle 18. The grinding wheel 14then is rotated and suitably moved axially to efiect a desired dressingof the side thereof against which the tip of tool 52 has been disposed.Particularly if the tool 52 is positioned relative to the horizontalaxis of grinding wheel 14 so that there is substantially little verticalspace therebetween, it will be seen that by reciprocating the chuck 10in opposite directions as indicated by the arrows in Fig. 2, effectivedressing of the front side of the grinding wheel, as viewed in Fig. 2,may be effected. Such reciprocation of the chuck 10 is accomplished byconventional mechanism within the grinding machine of which the chuck 10is a part and in which the chuck is reciprocable upon guideways bysuitable linkage or otherwise. The chuck 10 normally hold work pieces tobe ground by wheel 14 as the pieces are reciprocably moved by the chuck10 relative to wheel 1.

Further, by suitable positioning of the base 20, arm 36, and tool head48, the rear face of wheel 14 may be dressed by operations similar tothose described above relative to the front side of said wheel.

In addition, when it is desired to dress the curved face of the wheel14, as shown in Fig. 4, particularly if it is desired not to disturb thevertical position of wheel 14 from the chuck 10, it may be that it ispreferable to use the fiat face 22 of base member 20 so as to disposethe axis of bearing means 30 and 38 as close as possible to the uppersurface of chuck 10. Then, by positioning the arm 36 and head 48otherwise as indicated in Fig. 4 relative to grinding wheel 14, saidcurved face of the wheel readily may be ground particularly by not onlyrotating wheel 14 but also moving it axially of arbor 16, whereby theentire width of the curved face may be dressed.

From the foregoing, it will be seen that an extremely simple yet highlyeffective grinding wheel dressing device is provided which operates uponthe basic principle of permitting the dressing tool to be moved to thegrinding wheel whenever possible rather than vice versa, therebypermitting a given setting of a grinding wheel relative to a Work pieceon the grinding machine being maintained, yet making it possible for thewheel to be dressed in the midst of a grinding operation. Severalsupporting surfaces are formed upon the base member of the dressingdevice and a simple but accurate mounting means for a tool supportingarm permit a wide range of adjustment of said arm and a tool holdercarried in the outer end thereof relative to a grinding wheel. Suitablemeans also are provided for maintaining the various elements in alldesired positions to which said elements have adjustably been moved.Further, the dressing device is relatively light in weight, compact andsmall in size so as to require little storage space, and inexpensive toproduce. Also, as seen from Fig. 2 particularly, the entire dressingdevice 12, though narrow, is balanced laterally as viewed in said frameas, a result of arm 36 being disposed intermediately of the surfaces 22and 24 in a transverse direction.

It will also be seen from Figs. 1 and 4 that a further advantage isafforded by the dressing device relative to balance, Due to the factthat the axis of bearing means 30 and 38 is relatively close to fiatsurface 24 and even closer to flat surface 22 than to the opposite edgeof base member 20 to which the numeral 12 points in Fig. 1, there is notendency for the device 12 to tip regardless of the position in whicharm 36 is disposed relative to slot 32 or the flat surface 22 or 24 uponwhich the device is resting upon a grinding machine. Hence, due to theassgaas position of aperture 30 relative to fiat surfaces 22 and 24, thedevice is not top-heavy in any intended position of arm 36 even whenresting upon the chuck 10 or while being positioned thereon relative togrinding wheel 14, re gardless of whether the magnets of the chuck areener gized or not.

While the invention has been shown and illustrated in its preferredembodiment, and has included certain details it should. be understoodthat the invention is not to be limited to the precise details hereinillustrated and described since the same may be carried out in otherWays falling within the scope of the invention as claimed.

I claim:

1. A device for dressing the grinding wheel of a grinding machine andcomprising in combination, a base member having a flat surface thereonextending transversely to the main plane of said member and arranged tobe disposed upon a supporting surface of a grinding machine such as theface of a magnetic chuck thereon, whereby said base member extendsvertically from said supporting surface, said base member having bearingmeans extending parallel to said flat surface and positioned nearer oneend of said fiat surface than the other and said base member also havingan arcuate slot therein comprising a segment of a circle described aboutthe axis of said bearing means, an arm pivotally supported at one end bysaid bearing means and provided with clamping means intermediately ofthe ends of said arm and extending through said slot and operable toclamp said arm adjustably in desired angular positions relative to theaxis of said bearing means between a position extending toward saidother end of said fiat surface and a position substantially vertical tosaid flat surface, a head rotatably supported by the other end of saidarm for movement about an axis parallel to that of said bearing means,said head having means to hold a dressing tool, and means operable tolock said head in any desired position of adjustment about the axisthereof to support a dressing tool as desired relative to any surface ofa grinding wheel to be dressed thereby.

2. A device for dressing the grinding wheel of a grinding machine andcomprising in combination, a base member having a plurality of flatsurfaces extending transversely to the main plane of said member alongdifferent edges thereof and at substantially 90 to each other,

said surfaces selectively being arranged to be disposed upon asupporting surface of a grinding machine such as the face of a magneticchuck thereon, whereby said base member extends vertically from saidsupporting surface, said base member having bearing means extendingtransversely thereto at different distances from said flat surfaces,both of which distances are less than half the lengths of said flatsurfaces, and an arcuate slot therein comprising a segment of a circledescribed about the axis of said bearing means, whereby said bearingmeans is positionable selectively at different distances from saidsupporting surface according to the selected fiat surface said memberpositioned against said supporting surface, an arm pivotally connectedat one end to said bearing means and including clamping means extendingthrough said slot and operable to clamp said arm adjustably in desiredangular positions relative to said bearing means, a head rotatablysupported by the other end of said arm for movement about an axisparallel to said bearing means and said supporting: surface, said headhaving means to hold a dressing tool and means operable to lock saidhead in any desired position of adjustment about the axis thereof tosupport a dressing tool as desired relative to any surface of a grindingwheel to be dressed thereby.

3. The device according to claim 2 in which the length of said flatsurfaces is substantially greater than the width thereof and said arm ispositioned substantially centrally between the sides of said fiatsurfaces, thereby affording balance to said device when either of saidflat surfaces of said base member are disposed upon a horizontal face ofa magnetic chuck or the like.

4. The device according to claim 2 in which the arm is slidable againsta flat planar surface adjacent said arcuate slot comprising a clampingsurface perpendicular to said fiat surfaces upon said base member, saidclamping means holding said arm intermediately of the ends thereoffirmly against said planar surface.

References Cited in the file of this patent UNITED STATES PATENTS

